hypervisor: Fix clippy empty_line_after_doc_comments

Fix clippy warning empty_line_after_doc_comments reported by rustc
1.83.0 (90b35a623 2024-11-26).

Signed-off-by: Ruoqing He <heruoqing@iscas.ac.cn>

hypervisor/src/kvm/riscv64/aia.rs

@@ -31,7 +31,6 @@ pub struct AiaImsicsState {}
 
 impl KvmAiaImsics {
     /// Device trees specific constants
-
     fn version() -> u32 {
         kvm_bindings::kvm_device_type_KVM_DEV_TYPE_RISCV_AIA
     }